Comparison of in situ sediment remediation amendments: Risk perspectives from species sensitivity distribution.

Contaminated sediment is a major issue for aquatic environments, but attention must be kept even during remediation activities that can negatively affect resident biota especially when applied in situ. For the first time, the species sensitivity distribution (SSD) approach was applied to amendments used for in situ sediment remediation considering 39 papers including both freshwater (F) and saltwater (S) effect data (i.e. n = 17 only F, n = 19 only S, and n = 3 both F and S). Toxicity data related to the application of activated carbon (AC), nano-Zero-Valent-Iron (nZVI), apatite (A), organoclay (OC) and zeolite (Z) were collected and analyzed. SSD curves were constructed by lognormal model providing comprehensive comparisons of the sensitivities of different species to the relative testing methods. Results indicated that Bacteria were the most sensitive group of testing organisms, while Crustaceans were the less sensitive. The hazardous concentration for 5% of the affected species (HC5) were derived to determine the concentration protecting 95% of the species. OC, A and Z presented both acute and chronic toxicity. The HC5 values in descending order are: AC (4.79 g/L) > nZVI (0.02 g/L) > OC, A and Z (1.77E-04 g/L). AC and nZVI can be considered safer than OC, A and Z in sediment remediation activities, even if in situ long-term effects remained still underexplored.

Automated culture of aquatic model organisms: shrimp larvae husbandry for the needs of research and aquaculture.

Modern research makes frequent use of animal models, that is, organisms raised and bred experimentally in order to help the understanding of biological and chemical processes affecting organisms or whole environments. The development of flexible, reprogrammable and modular systems that may help the automatic production of 'not-easy-to-keep' species is important for scientific purposes and for such aquaculture needs as the production of alive foods, the culture of small larvae and the test of new culture procedures. For this reason, we planned and built a programmable experimental system adaptable to the culture of various aquatic organisms, at different developmental stages. The system is based on culture cylinders contained into operational tanks connected to water conditioning tanks. A programmable central processor unit controls the operations, that is, water changes, temperature, light irradiance, the opening and closure of valves for the discharge of unused foods, water circulation and filtration and disinfection systems, according to the information received by various probes. Various devices may be set to modify water circulation and water changes to fulfil the needs of given organisms, to avoid damage of delicate structures, improve feeding performances and reduce the risk of movements over the water surface. The results obtained indicate that the system is effective in the production of shrimp larvae, being able to produce Hippolyte inermis post-larvae with low mortality as compared with the standard operation procedures followed by human operators. Therefore, the patented prototype described in the present study is a possible solution to automate and simplify the rearing of small invertebrates in the laboratory and in production plants.

A pilot evaluation of the effect of defibrotide in patients affected by peripheral arterial occlusive disease.

This was a random double-blind study versus placebo designed to assess the effectiveness and tolerability of defibrotide in patients with chronic peripheral vascular disease (PVD), Leriche stage II. A total of 20 male outpatients (mean age 58.8 years) were selected and treated with placebo for 2 weeks (run-in period), and then allocated randomly to treatment with defibrotide (200 mg/day, intramuscular, n = 10) or matched placebo (n = 10) for 90 days. Before intake and at 15, 30, 60, and 90 days of treatment, each patient received a Doppler ultrasound examination of the lower limbs, and the residual perfusion index (Winsor) was calculated at rest and immediately after a symptom-limited treadmill test. Absolute walking distance was measured in addition. Blood samples were taken for routine laboratory tests before intake and at 30 and 90 days of treatment. All patients completed the trial without adverse effects; no meaningful alterations of laboratory test returns were detected. Patients receiving defibrotide showed a significant increase of the Winsor index after exercise at 90 days versus basal (mean 0.47 +/- 0.04 vs. 0.43 +/- 0.05, p less than 0.05), and a parallel increase of walking distance (basal 288 +/- 42.3 m vs. 368 +/- 46.6 at 60 days, p less than 0.05, and 407 +/- 64.3 m at 90 days, p less than 0.01). No improvement was seen in the placebo group. These preliminary results suggest that defibrotide may prove beneficial to patients with PVD; further studies are needed to find the most appropriate dosage regime.